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    <meta charset="UTF-8" />
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    <title>Document</title>
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    <script>
      // 表示某某个数组是否包含给定的值 返回的是布尔值
      let ary = [1, 2, 3];
      //   let result = ary.includes(4);
      let result = ary.includes(2);
      // console.log(result);
      let arr = [1, 3, 5, 6];
      let re = arr.includes(3);
      console.log(re); //查询数组arr中是否包含3这个元素 如果有就返回true,没有就返回false
    </script>
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